"Laziness", CelloDad is fond of saying, "is the mother of invention". CelloDad is one of the most inventive people I have ever met. I have learned many tricks from him over the years we have been together.
One effective way to get things done is to hold back the urge to do something, but instead to simply wait until the problem goes away. This approach works particularly well for dusty cars. Is your car covered in mud, or liberally dusted in tree pollen? Take heart: if you wait long enough, a good thunderstorm will eventually visit your parking spot, the heavens will open, and torrential rain will wash away all that dirt and dust, and leave your car sparkling.
I have applied this tactic many times, to great effect, and with satisfyingly little effort.
It saves you from releasing nasty chemicals, that might lurk in your car soap or waxing finish, into the environment. And it saves a lot of water. It also saves you a lot of work of the kind that requires you to take an extra shower: more water savings.
But once in a while you can't wait for the saving rain.